Mercurial > hg > nginx
annotate src/os/unix/ngx_linux_aio_read.c @ 9112:d59277dd3d8c
QUIC: fixed post-close use-after-free.
Previously, ngx_quic_close_connection() could be called in a way that QUIC
connection was accessed after the call. In most cases the connection is not
closed right away, but close timeout is scheduled. However, it's not always
the case. Also, if the close process started earlier for a different reason,
calling ngx_quic_close_connection() may actually close the connection. The
connection object should not be accessed after that.
Now, when possible, return statement is added to eliminate post-close connection
object access. In other places ngx_quic_close_connection() is substituted with
posting close event.
Also, the new way of closing connection in ngx_quic_stream_cleanup_handler()
fixes another problem in this function. Previously it passed stream connection
instead of QUIC connection to ngx_quic_close_connection(). This could result
in incomplete connection shutdown. One consequence of that could be that QUIC
streams were freed without shutting down their application contexts. This could
result in another use-after-free.
Found by Coverity (CID 1530402).
author | Roman Arutyunyan <arut@nginx.com> |
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date | Mon, 22 May 2023 15:59:42 +0400 |
parents | f01ab2dbcfdc |
children |
rev | line source |
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3052 | 1 |
2 /* | |
3 * Copyright (C) Igor Sysoev | |
4412 | 4 * Copyright (C) Nginx, Inc. |
3052 | 5 */ |
6 | |
7 | |
8 #include <ngx_config.h> | |
9 #include <ngx_core.h> | |
10 #include <ngx_event.h> | |
11 | |
12 | |
13 extern int ngx_eventfd; | |
14 extern aio_context_t ngx_aio_ctx; | |
15 | |
16 | |
17 static void ngx_file_aio_event_handler(ngx_event_t *ev); | |
18 | |
19 | |
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Fixing Linux AIO syscalls return value handling:
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20 static int |
3052 | 21 io_submit(aio_context_t ctx, long n, struct iocb **paiocb) |
22 { | |
23 return syscall(SYS_io_submit, ctx, n, paiocb); | |
24 } | |
25 | |
26 | |
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27 ngx_int_t |
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28 ngx_file_aio_init(ngx_file_t *file, ngx_pool_t *pool) |
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29 { |
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30 ngx_event_aio_t *aio; |
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31 |
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32 aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t)); |
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33 if (aio == NULL) { |
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34 return NGX_ERROR; |
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Valentin Bartenev <vbart@nginx.com>
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35 } |
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Refactored sendfile() AIO preload.
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36 |
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Refactored sendfile() AIO preload.
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37 aio->file = file; |
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38 aio->fd = file->fd; |
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39 aio->event.data = aio; |
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40 aio->event.ready = 1; |
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41 aio->event.log = file->log; |
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Refactored sendfile() AIO preload.
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42 |
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43 file->aio = aio; |
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44 |
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45 return NGX_OK; |
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Refactored sendfile() AIO preload.
Valentin Bartenev <vbart@nginx.com>
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46 } |
ccad84a174e0
Refactored sendfile() AIO preload.
Valentin Bartenev <vbart@nginx.com>
parents:
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47 |
ccad84a174e0
Refactored sendfile() AIO preload.
Valentin Bartenev <vbart@nginx.com>
parents:
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48 |
3052 | 49 ssize_t |
50 ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset, | |
51 ngx_pool_t *pool) | |
52 { | |
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
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53 ngx_err_t err; |
3294
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
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54 struct iocb *piocb[1]; |
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
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55 ngx_event_t *ev; |
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
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changeset
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56 ngx_event_aio_t *aio; |
3052 | 57 |
3294
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
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58 if (!ngx_file_aio) { |
3052 | 59 return ngx_read_file(file, buf, size, offset); |
60 } | |
61 | |
5980
ccad84a174e0
Refactored sendfile() AIO preload.
Valentin Bartenev <vbart@nginx.com>
parents:
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62 if (file->aio == NULL && ngx_file_aio_init(file, pool) != NGX_OK) { |
ccad84a174e0
Refactored sendfile() AIO preload.
Valentin Bartenev <vbart@nginx.com>
parents:
4412
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63 return NGX_ERROR; |
3052 | 64 } |
65 | |
5980
ccad84a174e0
Refactored sendfile() AIO preload.
Valentin Bartenev <vbart@nginx.com>
parents:
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changeset
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66 aio = file->aio; |
3052 | 67 ev = &aio->event; |
68 | |
69 if (!ev->ready) { | |
70 ngx_log_error(NGX_LOG_ALERT, file->log, 0, | |
71 "second aio post for \"%V\"", &file->name); | |
72 return NGX_AGAIN; | |
73 } | |
74 | |
75 ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0, | |
6480 | 76 "aio complete:%d @%O:%uz %V", |
3052 | 77 ev->complete, offset, size, &file->name); |
78 | |
79 if (ev->complete) { | |
80 ev->active = 0; | |
81 ev->complete = 0; | |
82 | |
83 if (aio->res >= 0) { | |
84 ngx_set_errno(0); | |
85 return aio->res; | |
86 } | |
87 | |
88 ngx_set_errno(-aio->res); | |
4076
37da005a5808
Bugfix: open_file_cache lost is_directio flag.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3777
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89 |
37da005a5808
Bugfix: open_file_cache lost is_directio flag.
Maxim Dounin <mdounin@mdounin.ru>
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90 ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, |
37da005a5808
Bugfix: open_file_cache lost is_directio flag.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3777
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91 "aio read \"%s\" failed", file->name.data); |
37da005a5808
Bugfix: open_file_cache lost is_directio flag.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3777
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92 |
3052 | 93 return NGX_ERROR; |
94 } | |
95 | |
96 ngx_memzero(&aio->aiocb, sizeof(struct iocb)); | |
97 | |
98 aio->aiocb.aio_data = (uint64_t) (uintptr_t) ev; | |
99 aio->aiocb.aio_lio_opcode = IOCB_CMD_PREAD; | |
100 aio->aiocb.aio_fildes = file->fd; | |
101 aio->aiocb.aio_buf = (uint64_t) (uintptr_t) buf; | |
102 aio->aiocb.aio_nbytes = size; | |
103 aio->aiocb.aio_offset = offset; | |
104 aio->aiocb.aio_flags = IOCB_FLAG_RESFD; | |
105 aio->aiocb.aio_resfd = ngx_eventfd; | |
106 | |
107 ev->handler = ngx_file_aio_event_handler; | |
108 | |
109 piocb[0] = &aio->aiocb; | |
110 | |
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
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111 if (io_submit(ngx_aio_ctx, 1, piocb) == 1) { |
3777
cd04f652478c
update event flags after successful io_submit()
Igor Sysoev <igor@sysoev.ru>
parents:
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112 ev->active = 1; |
cd04f652478c
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Igor Sysoev <igor@sysoev.ru>
parents:
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113 ev->ready = 0; |
cd04f652478c
update event flags after successful io_submit()
Igor Sysoev <igor@sysoev.ru>
parents:
3294
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114 ev->complete = 0; |
cd04f652478c
update event flags after successful io_submit()
Igor Sysoev <igor@sysoev.ru>
parents:
3294
diff
changeset
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115 |
3052 | 116 return NGX_AGAIN; |
117 } | |
118 | |
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
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119 err = ngx_errno; |
3052 | 120 |
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
|
121 if (err == NGX_EAGAIN) { |
3052 | 122 return ngx_read_file(file, buf, size, offset); |
123 } | |
124 | |
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
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125 ngx_log_error(NGX_LOG_CRIT, file->log, err, |
3052 | 126 "io_submit(\"%V\") failed", &file->name); |
127 | |
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
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128 if (err == NGX_ENOSYS) { |
3294
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
diff
changeset
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129 ngx_file_aio = 0; |
3052 | 130 return ngx_read_file(file, buf, size, offset); |
131 } | |
132 | |
133 return NGX_ERROR; | |
134 } | |
135 | |
136 | |
137 static void | |
138 ngx_file_aio_event_handler(ngx_event_t *ev) | |
139 { | |
140 ngx_event_aio_t *aio; | |
141 | |
142 aio = ev->data; | |
143 | |
144 ngx_log_debug2(NGX_LOG_DEBUG_CORE, ev->log, 0, | |
145 "aio event handler fd:%d %V", aio->fd, &aio->file->name); | |
146 | |
147 aio->handler(ev); | |
148 } |